A round baling apparatus of the fixed chamber type may comprise a baling chamber with rollers and a rearward section of the chamber with rollers being moveable in order to act as a door to release a completed bale from the bale chamber.
For a baling apparatus of the nonstop type as disclosed in the document WO 2013/014291 A1, the baling apparatus consists of two chambers, a first bale forming chamber and a second bale forming chamber. The second bale forming chamber has a standard bale density control system using the main chamber door to move and squeeze the crop into the predefined cylindrical shape. The door moves from a zero position in one direction thereafter only. The first bale forming chamber is also provided with a density control system and provides density control with a different method.